That all changed when I finally unboxed my Kuman 3.5″ LCD display, (a steal at $20) which my in-laws gave to me for Christmas (they went through my Amazon wishlist for gift ideas). They had no idea what it was, but figured I’d like it, which I do!
With a 3.5″ diagonal and 480 by 320 resolution, this screen isn’t meant for reading web pages or PDFs or writing code, documents, or spreadsheets. It’s meant to be a display for an IoT project that doesn’t need to display a lot of information, such as a weather app, smart thermostat, or even low-res videogames.
The screen’s not just an output device, but an input device as well, since it’s touch-sensitive. Once you’ve installed the driver, the Pi treats the screen as if it were another mouse, treating taps as mouse clicks, and the location of your tap as mouse coordinates.
The screen plugs directly into the Pi’s GPIO (General Purpose Input/Output), a 40-pin connector located along the top edge of the board, which it uses for power. It’s also what physically holds the screen to the Raspberry Pi.
The video signal is fed to the screen through a U-shaped HDMI connector that connects the Raspberry Pi’s HDMI port to the screen’s HDMI port.
I’ll post the results of my noodling with this new Raspberry Pi/screen combo here on Global Nerdy. It should be interesting!
I recently got a Mokin 10-in-1 USB-C dongle for use with my work computer, a 2019 16″ MacBook Pro, whose only connectors are 4 Thunderbolt/USB-C ports and a 3.5 mm audio jack.
The dongle worked like a charm out of the box with the notable exception of one part: The Ethernet port. I had a pretty good guess why this was happening and how to fix it.
The problem and the plan
Most dongle vendors are integrators. They may manufacture the cases and simpler electronics, but they purchase lot (or all of) the fancier tech from manufacturers, such as networking chips.
Here’s a pic showing a Mokin dongle and its internals:
My plan was to find the manufacturer of the networking chip inside my dongle, then find their webpage, then hopefully find a driver.
Here’s what I did.
Step 1: Identifying the vendor
With the dongle plugged into my MacBook, I opened the Apple menu and selected About This Mac. This window appeared:
I clicked the System Report… button, which opened the System Report window:
This window provides a run-down of the hardware, software, and networking on your Mac. Its Hardware list provides information about the hardware in and attached to the computer. A lot of peripherals have information such as vendor IDs encoded to them, and you can use System Report to find it.
I expanded the Hardware menu and selected the USB item. The USB Device Tree list appeared in the window’s right pane.
I then went through the USB 3.1 Bus entries in the USB Device Tree list in search of an entry containing the word LAN. Once I found that entry, I clicked on it, which then caused its details to appear in the lower part of the right pane.
I found the information that I needed: the Vendor ID, and better still, an actual vendor name: Realtek.
(They would be well-served by a team that could do a half-decent job localizing the language on their installer.)
Step 4: Enable wired networking
With the driver installed, it’s time to make wired networking happen!
Open System Preferences. To add wired networking, you’ll need to add a new networking service, which you do by clicking the + button at the bottom of the menu on the left side of the window: You’ll be asked to select the interface and provide a name for the new networking service. Select USB 10/100/1000 LAN from the Interface menu, and enter whatever you like for in the Service Name field. I entered “Wired” for mine:
I clicked the Create button, which created the service and dismissed the dialog box. The new service, named Wired, appeared in the menu on the left side, with Not Connected as its subtitle.
I clicked the Apply button…
…and the Wired service went from Not Connected to Connected:
Now it was time to test the connection. I shut off wifi and ran Speedtest.net on my wired connection. The results shown below are for my work computer, which uses a VPN that I need to always keep on (or there will be. consequences):
That’s a good deal faster than I get on wireless, and I’m sure I’ll get better speeds on my personal computer when it’s not on a VPN.
The kind of computer that hasn’t been seen since the 1980s
Let’s quickly take stock of what you get with just the Raspberry Pi 400, never mind the kit:
A fully-equipped computer with a decent processor, decent RAM, wifi/wired/Bluetooth networking with 2 fast USB ports to spare once you’ve plugged a mouse into the slower one.
A computer that you can do hardware experiments with, thanks to its GPIO pins, and an abundance of hobbyist-focused expansion kits.
A computer that you can plug into your TV.
A computer that costs $100.
There hasn’t been a computer like this since the machines pictured below came out…
…and those machines couldn’t hold a candle to the proper desktops of that era.
On the other hand, you’ll find that the Raspberry Pi 400 can easily keep up with the sort of computer that gets issued for standard office work. You could easily use it to do schoolwork or office work, and it’s actually a decent Linux software development machine and retro-style gaming console, too! And with its expansion capabilities, it’s an excellent machine for IoT and sensor projects.
This is the sort of machine that children of the 1980s and early 1990s learned on, many of whom are today’s techies…
…and this machine will probably be the machine that a lot of children of the 2020s will cut their programming teeth on, and who’ll be the techies of the 2040s and 2050s.
Given a choice between a Chromebook and a Raspberry Pi 400, I’d take the Pi, because I can do a lot more with it. In fact, I might be able to do a lot of my new job with it (which is something I might try soon, just to see what happens).
By the bye, keep an eye on this blog for a new feature: Cobra Pi, which covers programming on the Raspberry Pi, and whose motto is: “Code hard! Fail fast! No latency!”